Back in the day, they wouldn't have let the likes of Joey Ramone and Patti Smith through their door. Yet later this month, they'll be auctioning off their most collectible bits'n'pieces. That's right - Christie's is having its first punk-themed auction on November 24 in New York.

Clearly, the commodification of punk happened long before this - but does anyone know when exactly?

Was it with grunge and the Nevermind effect? Sonic Youth famously claimed that 1991 was "the year punk broke", naming a tour film (featuring Nirvana, amongst others) after the phrase. In the US the alt-rock boom led to "alternative" clothes shops like Hot Topic popping up in the local mall. Characters like Beavis and Butt-head's Daria and Roseanne's Darlene appeared on TV: sullen and contemplative, their darkly sarcastic quips were beamed into your house every week.

Or was it with emo? The Daily Mail-hated scene took some of punk's aesthetic and musical flavours and coloured themselves into the mainstream with the rise of bands like My Chemical Romance and Fall Out Boy. They brushed the fringes out of their hair, battered their Guyliner-fluttering eyelashes and sold millions of records. Suddenly singing about suicide became big, big business.

But even in a world where a reality TV star can "go punk" for a photo shoot (ie spike their hair a bit), Christie's auction proves that the genre has gone to the next level of sellability. Who is this new generation of post-baby boomers who will pay top dollar for a flyer of the Sex Pistols/Clash/Buzzcocks legendary Screen on the Green gig?

According to their pop culture man, Simeon Lipman: "The generation who can now afford to buy this stuff is interested in different things. They're not as interested in the Beatles as they are in the Sex Pistols or Nirvana. Ten years ago, punk memorabilia probably wouldn't be something we'd be auctioning here. But now, people of a certain age have a certain ability to splurge on this material."

Does that mean in 30 years someone will be spending money on a rare Reverend and the Makers hand towel? We're shuddering at the thought.

For now there are 120 pieces of amazing material (records, photos and promotional items) to enjoy from the Velvet Underground to Blondie. Our favourites? An original Patti Smith poem and a Malcolm McLaren/Vivienne Westwood bondage jacket from the SEX shop.